The fish extractor can be used to either catch double the amount of fish with no Fishing experience gained, or used to double the amount of experience with no fish caught. Once activated, there is no way to turn the fish extractor off; it does not require bait and lasts for 100 charges.

Once all of the charges have been used, the extractor will break and a message in chat will appear which says "After sustained use, the dwarven fish extractor breaks apart in your hands." If multiple extractors are created they will stack and act as one tool with all the charges (a total of charges equal to (Y x 100) where "Y" is the amount in the stack).

If the double experience mode is used with a pair of Fishing experience-boosting gloves from the Fist of Guthix Reward Shop, the extra experience from the gloves will be applied before the experience is doubled. In the case of raw swordfish, at least 400 experience will be gained per fish caught.

During certain bonus XP events (such as Double XP Weekends and the 2016-17 New Year 10% bonus XP event) the dwarven fish extractor cannot be used. Even if the item is in the player's inventory, it will not activate in either double experience or double resource mode, and charges will not be used.

Fishing for raw wobbegongs will still yield 100 wobbegongs per fishing spot.